Drives for people movers, such as escalators and moving walkways, typically fall into three main categories: inside the stepband direct drives; outside the stepband direct drives; and outside the stepband chain drives. Drives located inside the stepband typically have the advantage of keeping the pit area free for escalator maintenance. However, the drives located in the stepband can be difficult to service, and/or can be limiting in package space due to their location within the stepband.
Of the drives located outside the stepband, the chain drive is the most common. This type of drive often has the advantage of keeping all the serviceable items in the escalator pit. However, it can also have the disadvantages of being relatively less efficient, using up a relatively large amount of pit room, and/or being environmentally unfriendly due to having oil on the exposed main drive chain. Other systems with the drive located outside the step have failed to locate the serviceable side of the drive in the pit.